The invention relates to a device for disposal of liquid media such as coolant and lubricant fluids, containing production residues, such as chips from industrial processes in which these media can be conveyed from at least one accumulation site through gutters and/or pipes to a recycling container and from the recycling container through a pipe connected thereto close to the bottom to at least one collecting tank.
Devices of this kind are known in a variety of embodiments, for example from European patent document EP 0 593 005 A1, German patent documents DE 44 30 959 A1, DE 44 36 003 A1, and DE 195 01 921 A1 as well as U.S. Pat. Nos. 5,590,678, 5,575,307, and 5,732,826, which have common ownership and overlapping inventorship with the instant application. The media are always delivered from the recycling container to the collecting tank by pumps.
One disadvantage of these known devices is that it is difficult to convey foamed media that contain considerable air, and pumps with especially large dimensions are required.
The goal of the invention is to be able also to convey foamed media from the recycling container to the collecting tank at a low equipment cost.
This goal is achieved in a device of the type descried above by dividing the recycling container with a pressure-tight partition containing an operable valve into an upper supply chamber and a lower delivery chamber, with a compressed air line with a switchable compressed air inlet valve being connected to the upper area of the delivery chamber and with a vent line with a switchable vent valve being connected to the same area, and with at least two sensors being located in the delivery chamber, spaced vertically apart from one another, and responding to the level of the media in the delivery chamber.
With the valve in the partition closed and the vent valve closed and with the compressed air inlet valve open, a pressure is generated in the delivery chamber by which the media can be delivered from the delivery chamber through the pipe into a collecting tank without the use of pumps being required.
Advantageously, at least one sensor that responds to the level of the media is located in the delivery chamber, said sensor serving as protection against overfilling. The pipe that leads to the collecting tank can contain a check valve that prevents backward flow of media from this pipe into the delivery chamber.
The vent line can terminate in the ambient atmosphere or in the upper area of the supply chamber. Venting to the upper area of the supply chamber has the advantage that entrained particles of media can be recycled and not pollute the environment. On the one hand, the valve in the partition can be designed as a switching valve that can be controlled in conjunction with the requirements of the operation of the device. On the other hand, the valve in the partition can be an automatic valve with a ball that floats in the delivery chamber as a function of the level of the media and thus closes the valve at a certain level. As a result, this valve is closed when the level of the media in the delivery chamber rises, and opens again when the level falls.
According to one preferred embodiment of the invention, the recycling container is open at the top and at least one supply line inclined relative to the recycling container for the media from at least one accumulation site located higher up terminates in the upper area of the supply chamber. This assumes that the accumulation site(s) of the media containing production residues is/are located higher than the delivery chamber in the recycling container and consequently the media can flow into the supply chamber under the influence of gravity.
The supply line can be designed as a pipe or gutter.
According to another preferred embodiment of the invention, the recycling container is sealed off at the top in a pressure-tight manner, with at least one suction line terminating in the upper area of the supply chamber. The suction line is connected at the other end to a gutter that can be filled with media from at least one accumulation site. The supply chamber and the delivery chamber in the recycling container can be subjected to reduced pressure by an evacuation device with an exhaust air outlet and containing switchable vacuum valves. The level of the accumulation site(s) relative to the level of the recycling container can be arbitrary because the media can flow through the suction line(s) into the supply chamber under the influence of the reduced pressure in the supply chamber.
Advantageously, a sensor can be provided in the end area of the gutter facing the suction line that responds to the level of the media in this end area. The sensor makes it possible for the evacuating device to be set operating in proper time.
According to another preferred embodiment of the invention, a plurality of recycling containers are provided with a pipe connected thereto and containing a check valve. A gutter and a suction line are connected upstream thereof. Sensors are provided in the delivery chamber, a compressed air line, and a vent line. An intermediate container is added in each case between the gutter and the suction line, with each of the containers containing at least one sensor that responds to the level of the media in the container. The plurality of recycling containers are connected in parallel with a single evacuation device. A vacuum switching valve is included in each vacuum main line that connects a recycling container with the evacuating device. As a result, disposal of liquid media containing production residues can be simplified, said residues coming from various accumulation sites at which liquid media containing production residues are not necessarily located simultaneously. This is the case for example when the accumulation sites are associated with various machine tools that can operate simultaneously or individually.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.